I like this paperback very much for its photos: much of the space on pages is covered by great exciting pictures with valuable comments under each image.
This book is the unsurpassed reference on how to choose the best class for SCCA autocross; it has excellent descriptions of requirements of each class, actual for 2006 season.
The major drawback of this book is the lack of references section. When you complete this book, you have no directions where to proceed; you have no idea of further reading. When the author quotes somebody, he gives no source. I see no shame in exposing the source. All prominent writers are dwarves standing on the shoulders of giants (previous writers). There are also errors in the names of products: "Motul" damper on page 25 (should be "Moton"), "Scroth" on page 113 (should be "Schroth"). The second edition of this book is desired.
While most of the book is devoted to differences in SCCA classes, very little attention is given to driving techniques. For example, the author devotes only a quarter of textual page to "oversteer & understeer" with no illustrations. As a comparison, Carl Lopez in his famous title "Going Faster" gives 17 pages full of illustrations to explain these modes of car behavior. I highly recommend "Going Faster" to any autocrosser.
In addition to this book, I would recommend "Winning Autocross Solo II Competition" by R. H. Turner & J.B. Miles; and "Secrets of Solo Racing" by Henry A. Watts
If you need something deep on driving techniques (which apply to any motorsport, not just autocross), I would recommend "Competition Driving" by Alain Prost, "The Technique of Motor Racing" by Piero Taruffi, "Driving in Competition" by Alan Johnson and "Sports Car and Competition Driving" by Paul Frere.